Utilitarianism is mainly characterized by two elements: happiness and consequentialism. Utilitarian happiness is the biggest happiness which (supposetly) every human being looks for. In utilitarianism everything useful to happiness is good. Therefore, the name of the doctrine is utilitarianism, based on the principle of utility. Utility is found in every thing which contributes to the happiness of every rational being. The criterion of good and evil is balanced between individual's happiness and the happiness of the community, "each counting in an equal way" (Bentham, Introduction in the principles of morality and legislation). Consequentialism in utilitarianism is in the fact that an action must be judged for its consequences on the happiness of the largest number. That is: my search for happiness stops when it decreases the happiness of another individual or the happiness of the largest number, of the society or the community. As personal freedom is considered in respect of the freedom of other individuals and of the community, my freedom stops when it diminishes the freedom of another individual or the well-being of the society. We could say that utilitarianism is the continuation of Roman legislation, and its modern aspect is shown in the fact that utilitarianism adds an economical, legislative and political dimension to an ethical concept, that of happiness and well-being. The modern aspect of the doctrine will evolve throughout the 19th century, with Bentham, Mill and Sidgwick who succeeds in giving to this doctrine a practical and rational dimension which we can find in our modern society, in economics, politics and ethics.

"The continuing vitality of the greatest happiness system is not difficult to understand – it embodies a very natural and compelling model of rationality. This model, which dominates much of contemporary economics (as well as decision theory, "cost-benefit analysis", and "public choice theory") sees rational action as an attempt to maximise net utility (i.e. the result of summing the benefits and costs and subtracting the latter from the former). This view, which is frequently called "means-end" rationality, goes back (at least) to Aristotle. In the Nicomachean Ethics Aristotle asserts that "we cannot deliberate about ends but only about the means by which ends can be attained." If we assume, with Aristotle, that happiness is the "highest good attainable by action," and hence the aim of politics, we get something very like Bentham's view. Indeed it is tempting, and not implausible, to interpret philosophers as different as Adam Smith and Chairman Mao as agreeing that the goal of social institutions is the maximization of realizing that end.

Of course philosophers who share this vision of the proper function of social institutions like law and morality may differ on more than the best methods to attain it, as Aristotle noted, there is widespread agreement that happiness is the goal, but considerable disagreement as to what constitutes happiness. For Bentham the answer is simple: happiness is just pleasure and absence of pain. The value (or disvalue) of a pleasure (or pain) depends only on its intensity and duration, and can (at least in principle) be quantified precisely. Given this, we can reconstruct one line of Bentham's argument for the principle of UTILITY as something like the following:

The good of a society is the sum of happiness of the individuals in that society.

The purpose of morality is promotion of the good of society.

A moral principle is ideal if and only if universal conformity to it would maximize the good of society.

Universal conformity to the principle of UTILITY ("Act always so as to maximize total net balance of pleasures and pains") would maximize the good of society

____________________________________________________

Therefore the principle of UTILITY is the ideal moral principle."

(See the book: The Classical Utilitarians: Bentham and Mill, author: John Troyer, Professor of Philosophy at the University of Connecticut)

"The origin of the utilitarian doctrine is in the debate, which brought together, during the largest part of the 18th century, the philosophers of the "moral sense", Shaftesbury and Hutcheson who tried to find a natural foundation for the moral motivation of spontaneous benevolence that we feel for someone else and his happiness, and their criticisms (of those philosophers), which we describe as followers of Hobbes, who, nevertheless, was not utilitarian.
(…)
Utilitarianism joins a very long tradition of thought which goes back, to China, from Mo-Tseu for example, and in Greek philosophy, from, essentially, Aristotle and Epicurus. Then, it offers the paradox to be, with Kantianism, his contemporary and rival; always so alive as it was more than two centuries ago: Bentham's Principles of Morals and Legislation was published, indeed, in 1789, and Kant's Critic of Practical Reason in 1788. And, more specifically, it dominates the English-speaking world where, unlike in France, the Kantian philosophy had difficulty in being adopted. The critics which Mill sent to Kant in Utilitarianism in the name of the consequentialism still seem as valid as they were." (See, Introduction of Catherine Audard et Patrick Thierry, of the book: John Stuart Mill, L'utilitarisme Essai sur Bentham, PUF, 1998)

Even if utilitarianism exists since a long time, it seems to take a bigger importance in the 18th and 19th centuries, with the beginning of modern society and the end of the feudalism. Indeed, the industrial development which occured in Europe in the 18th century entailed important changes in the behaviour of individuals within the society. So, industrialization, in which France was, in the 18th century, the leading country, individualized the people of the society. That is, this new society (or community) which offered to the poorest, to averagely poor men and to the averagely rich men, to meet their needs without being obliged to be part of a clan or a family group. During the Middle Ages, the individual could not survive alone, the group was the only means of survival, whether it was within the city, the big villages or around a Lord's castle in the countryside. In the Middle Ages an individual could only survive if he was part of a group. The technological and scientific development and the discoveries of new lands, in 15th, 16th and 17th centuries, produced the society of the Enlightenment, society which gave birth to individualism and to the independence of private economy with regard to the State. It is thus in this context that the "laissez-faire policy" appeared, which bacame finally the creed of utilitarianism in the sense that as an individual is free to produce his own happiness, and is most aware to know what is convenient for him, but it also gave more responsibilities to the individual because the consequence of the individual's acts became very important and fundamental. Indeed, it is here, in this aspect of utilitarianism that we can see the french influence of Auguste Comte's altruism, and a general movement of a "humanization" of the European society. And as this society became richer and "mastered" a little more the nature in which it evolved, as it had financial and material means which brought a better material comfort it allowed, in the 18th century, an individualization of the persons, producing then the consideration of the other one as a unique individual in the same way as each one considered himself as a unique individual, and not as part of a group. Our modern society is then born.

The "laissez-faire" takes its origin in France. In 1683, during a meeting between Colbert (1619-1683) and a group of French traders managed by a certain Legendre, who, when Colbert asked the traders what the French State could do to help them, he answered this:

Let it be, such should be the motto of every public power, ever since the world is civilized ... A detestable principle that we want to grow but by the lowering of our neighbours! There is nothing but mischief and malignity of heart that are satisfied with that principle, and interest is opposed to it. Let it be (laissez-faire), damn it (morbleu) ! Let it be!! (J. Turgot: Eloge de Vincent de Gournay, Mercure, 1759)

Vincent de Gournay (1712-1759) popularized this motto which characterized the need of economic and individual freedom which reflects in the 18th century: "let make (laissez-faire), allow passing, the world goes by itself ". This need of freedom keeps pace with an increasing individualism which cannot exist without a certain altruism, which finally Auguste Comte expressed in the first half of the 19th century. Comte expressed a state mind which existed and evolved throughout the 18th century but which could not be clearly expressed because people were too busy freeing themselves, physically, economically and intellectually, that they did not manage to express this altruism born with individualism. Finally individual happiness lauded by utilitarianism comes inevitably along with an altruism, given that man can only be happy if the community is happy itself; it is thus necessary to respect the happiness of others by acting in a way that the consequences of my acts would produce happiness, or, at least, not cause misfortune to anyone.

Utilitarianism expressed a desire of freedom; it is then a form of liberalism. Indeed, in England, it evolved in two currents arisen from the influence of Bentham: an economic liberalism and a social liberalism. The need of freedom arising from the end of the 17th century and during the 18th century developed and expressesed itself much more clearly in the 19th century. Two currents appeared then: an economical liberalism which will become the capitalism in the 20th century, and a social liberalism which will become during the 19th and 20th centuries socialism and later on communism.